Epidermis & Keratinization Flashcards Preview

Dermatology > Epidermis & Keratinization > Flashcards

Flashcards in Epidermis & Keratinization Deck (19):
1

Squamous cell carcinoma characterized by?

Redness and scaling

2

Row of tombstones is indicative of?

Pemphigus vulgaris

3

Desquamation involves? (3 things)

1) Proteolysis of intercellular bonds via hydrolases
2) Organized dissolution of intercellular lipids
3) Keratinocytes shed singly without dry skin

4

Xerosis characterized by? (3 things)

Fine, white scale
Hyperkeratosis
May be itchy

5

Mechanism of xerosis (3 things)

1) Dehydration of keratinocytes due to decrease in Natural Moisturizing Factors
2) Decreased intercellular lipids
3) Failure to break intercellular bonds in organized fashion

6

5 endogenous causes of xerosis

Atopy
Ichthyosis vulgaris
Renal insufficiency
Lipid lowering medications
Malnutrition

7

Acanthosis

Hyperplasia of stratum spinosum due to proliferation

8

Hyperkeratosis

Hyperplasia of corneum due to increased production or reduced desquamation

9

Lichenification

Hyperplasia of spinosum and corneum due to scratching / rubbing

10

Keratosis pilaris

Hyperkeratosis (hyperplasia of corneum) due to retention
Tiny pink dots associated w/ hair follicles

11

Lichen simplex chronicus

Lichenification (hyperplasia of spinosum and corneum) due to rubbing and scratching

12

Ichthyosis vulgaris (cause, inheritance, age, appearance, association)

Most common disorder of cornification
Retention hyperkeratosis
Autosomal dominant
Appears in childhood
Fish scale appearance (polygonal)
Associated with atopic triad, hyperkeratosis pilaris, and hyper linear palms

13

Palmoplantar Keratoderma (cause, inheritance, 3 subtypes, and treatment)

Hyperkeratosis of palms and soles
Autosomal dominant and recessive
Due to keratin mutation
Diffuse - thick, yellow plaques; associated w/ hyperhidrosis (excess sweating)
Focal - Hyperkeratosis over pressure points
Punctate - Hyperkeratotic papules w/ warty apperance
Treated w/ paring hyperkeratotic areas, moisturizers, and humectants

14

Atopic dermatitis (cause, defect, sxs, tx)

Inflammation due to aberrant TH2 response
Filaggrin defect --> reduction in AA's --> dehydration of corneum
Itchy rash that favors flexural surfaces
Treat with topical steroid

15

Psoriasis (inflammation, sxs, tx)

Inflammation due to TH1 and TH17
Hyperplasia of spinosum (acanthosis) due to increased rate of cell turnover and inflammation
Variably itchy rash that favors extensor surfaces
Red plaques, thick adherent scale, and nail changes.
Tx w/ topical steroid

16

Atopic dermatitis (cause, defect, sxs)

Inflammation due to aberrant TH2 response
Filaggrin defect --> reduction in AA's --> dehydration of corneum
Itchy rash that favors flexural surfaces

17

Psoriasis (inflammation and sxs)

Inflammation due to TH1 and TH17
Faster cell turnover
Variably itchy rash that favors extensor surfaces
Red plaques, thick adherent scale, and nail changes.

18

SSSS (cause, sxs, treatment)

Due to exotoxin of staph aureus (Exofoliative toxins ET-A / B) attacking desmoglein 1
Toxins are renally excreted
Malaise, irritability, fever, PAIN
Cutaneous erythema starting at head and generalizing
Flacid bullae
Desquamation
Tx includes IV antibiotics

19

5 steps of keratinization

1) Enlargement and flattening of keratinocytes
2) Filaggrin-induced keratin assembly and cross-linking to form cornfield envelop
3) Lamellar granule lipids form hydrophobic barrier
4) Degradation of organelles to form anucleate cells
5) Apoptosis
Moving upwards the whole time